Just add a chromosome...

摘要

Genetic diseases might one day be treated by adding an entirely new chromosome to people's cells. A Canadian company has shown the approach could be a feasible method of gene therapy. Conventional gene therapy relies on modified viruses to insert the desired bit of DNA into a cell's genome. But viruses can carry only short sequences of DNA. And if the DNA lands in the wrong place, as happened to two boys in a French gene therapy trial, it can trigger cancer.